Journal of neurosurgery. Spine
-
Over the past decade, there has been a dramatic increase in the number of spinal fusions performed in the US and a corresponding increase in the incidence of adjacent-segment disease (ASD). Surgical management of symptomatic ASD consists of decompression of neural elements and extension of fusion. It has been shown to have favorable long-term outcomes, but the cost-effectiveness remains unclear. In this study, the authors set out to assess the cost-effectiveness of revision surgery in the treatment of ASD over a 2-year period. ⋯ In the authors' practice, revision decompression and extension of fusion provided a significant gain in health state utility for patients with symptomatic ASD, with a 2-year cost per QALY gained of $62,995. When indicated, revision surgery for ASD is a valuable treatment option for patients experiencing back and leg pain secondary to ASD. The findings provide a value measure of surgery that can be compared with future cost-per-QALY-gained studies of medical management or alternative surgical approaches.
-
Cervical arthroplasty is a valid option for patients with single-level symptomatic cervical disc diseases causing neural tissue compression, but postoperative heterotopic ossification (HO) can limit the mobility of an artificial disc. In the present study the authors used CT scanning to assess HO formation, and they investigated differences in radiological and clinical outcomes in patients with either a soft-disc herniation or spondylosis who underwent cervical arthroplasty. ⋯ Clinical outcomes of single-level cervical arthroplasty for soft-disc herniation and spondylosis were similar 3 years after surgery. There was a significantly higher rate of HO formation in patients with spondylosis than in those with a soft-disc herniation. The mobility of the artificial disc is maintained, but the long-term effects of HO and its higher frequency in spondylotic cases warrant further investigation.
-
Previous studies have demonstrated that patients with spinal fusion are at greater risk for adjacent-segment disease and require additional surgery. It has been postulated that excessive motion of a given motion segment unit (MSU) leads to an increased risk of disc degeneration. It is the authors' hypothesis that a greater increase in adjacent-segment motion will be observed following a 2-level versus a single-level anterior cervical discectomy and instrumented fusion (ACDF). Therefore, they undertook this study to determine the effect of single-level versus 2-level ACDF on the biomechanics of adjacent MSUs. ⋯ This study has shown that the biomechanics at adjacent levels to a cervical spine fusion are altered and that there is increased adjacent-segment motion at the levels above and below, after a 2-level compared with a 1-level ACDF.
-
Despite extensive study, no meaningful progress has been made in encouraging healing and recovery across the site of spinal cord injury (SCI) in humans. Spinal cord bypass surgery is an unconventional strategy in which intact peripheral nerves rostral to the level of injury are transferred into the spinal cord below the injury. This report details the feasibility of using spinal accessory nerves to bypass cervical SCI and intercostal nerves to bypass thoracolumbar SCI in human cadavers. ⋯ Both spinal accessory and intercostal nerves, accessible from a posterior approach in the prone position, can be successfully harvested and transferred to their respective targets in the cervical spinal cord and conus medullaris. As expected, the number of axons available to grow into the spinal cord diminishes distally along each nerve. To maximize axon "bandwidth" in nerve bypass procedures, the most proximal section of the nerve that can be transferred in a tension-free manner to a spinal level caudal to the level of injury should be implanted. This study supports the feasibility of SAN and intercostal nerve transfer as a means of treating SCI and may assist in the preoperative selection of candidates for future human clinical trials of cervical and thoracolumbar SCI bypass surgery.
-
Multicenter Study
Multicenter validation of a formula predicting postoperative spinopelvic alignment.
Sagittal spinopelvic imbalance is a major contributor to pain and disability for patients with adult spinal deformity (ASD). Preoperative planning is essential for pedicle subtraction osteotomy (PSO) candidates; however, current methods are often inaccurate because no formula to date predicts both postoperative sagittal balance and pelvic alignment. The authors of this study aimed to evaluate the accuracy of 2 novel formulas in predicting postoperative spinopelvic alignment after PSO. ⋯ The spinopelvic alignment formulas were accurate when predicting unsuccessful outcomes but less reliable when predicting successful outcomes. The preoperative surgical plan should be altered if an unsuccessful result is predicted. However, even after obtaining a predicted successful outcome, surgeons should ensure that the predicted values are not too close to unsuccessful values and should identify other variables that may affect alignment. In the near future, it is anticipated that the use of these formulas will lead to better surgical planning and improved outcomes for patients with complex ASD.